Fun with dry ice

Dry ice is a pretty amazing substance. It is made of solid CO2, and when it warms up it goes straight from the solid phase to the gaseous phase. This is called sublimation. There are many cool things you can do with dry ice. It’s a good way to teach about hot and cold (which is just the lack of heat), and the phases of matter. You should wear gloves and goggles for all of these.

Cool thing #1: Take a quarter and press it down against the dry ice. The gas escaping from around the quarter makes a loud noise. Be careful because the quarter might go flying.

Cool thing #2: Take some PVC pipe and create a tube with one end stopped up (it helps if the top of the open side is curved). Put a piece of dry ice in the bottom of the pipe and dip the open top end in some bubbles (like the kind you blow bubbles with). The gas form of the dry ice is many many times larger in volume than the solid form, so the gas escapes through the open end and blows bubbles for you. The cool part is that the bubbles are full of fog, and they sink quickly. When they hit the ground and pop, the fog escapes and it looks pretty cool.

Cool thing #3: Use the same PVC pipe from Cool thing #2 (you don’t need the curved piece for this), and attach a balloon to the top. Be sure that it is well sealed. Like I said, the gaseous form of dry ice is much larger in volume than the solid form, so it will blow up the balloon for you. It will even pop it if you hold it on for long enough. Definitely wear gloves and goggles.

Cool thing #4: Make root beer. Use dry ice to carbonate your beverage. You can find the recipe here. I suggest playing with the root beer extract and sugar amounts, tasting as you go so you get it just the way you like it!

Cool thing #5: Halloween approaches. So of course I must mention that you can make traditional Halloween sciency-looking potions by adding dry ice and food coloring to water in a beaker, flask, cylinder or burette of your choice. Don’t forget the clamps, goggles, lab coat and crazy hairdo.

There are all sorts of cool stuff you can do with dry ice, from making vortex cannons to quarter whistling. If you want to share any of your own ideas, leave a comment below.